Several vendors offer computer programs designed to assist businesses in lead generation. Ethics are an important consideration in the choice and implementation of such programs. The use of spyware, Trojans or other intrusive means of gathering information without the knowledge or consent of targeted individuals or entities is frowned upon. Mass unsolicited e-mail advertising (or spam) is also considered unethical by many, and it can result in electronic blacklisting.

Because lead generation is the first step of the sales process, both quality and quantity are important factors. Quality leads are leads that a salesperson has a good chance of closing, which means they must at least have the potential to become customers. Every lead list will have a number of junk leads – people who are not qualified to buy the product for some reason – but the smaller the percentage of bad leads, the less time salespeople will waste while processing that list. Quantity is also important because even a salesperson with a list of 100% good leads won't be able to close every one of them.
Sales leads are generated on the basis of demographic criteria such as FICO score (United States), income, age, household income, psychographic, etc. These leads are resold to multiple advertisers. Sales leads are typically followed up through phone calls by the sales force. Sales leads are commonly found in the mortgage, insurance and finance industries.